Description
Between June 2025 and February 2026, Iran refused to weaponise its nuclear programme despite recovering from Israeli-US strikes on its major facilities. Its stockpile stood at 440.9 kg of 60%-enriched uranium. Diplomatic off-ramps had closed with the E3 snapback in September 2025, the JCPOA had expired in October, and its regional allies had been severely weakened. Tehran had every material incentive for nuclear breakout. Realist proliferation theory predicts exactly that outcome. It did not happen.
An integrated strategic culture and ontological security framework explains this puzzle. Process-tracing three identity mechanisms across 150 coded elite statements and primary IAEA, intelligence, and diplomatic sources shows that ideational constraints causally prevailed over survival incentives, failed alliance guarantees, and organised hardline factional pressure. Shia jurisprudential prohibitions on nuclear weapons and Iran’s revolutionary self-narrative constrained decision-making even as material logic pointed toward weaponisation.
Senior IRGC commanders pressed the Supreme Leader to revoke his anti-nuclear fatwa; parliamentary factions echoed the demand in writing. He reaffirmed it regardless. This restraint held until Ali Khamenei’s death in the February 2026 war removed its institutional foundation.
The case constitutes a hard test against realist proliferation models, with direct implications for scholarship on coercive deterrence, nuclear decision-making, and identity-based restraint under acute geopolitical conflict.